Fire alarm cable buyers in New York

Sizes, counts and what each conductor does

The conductor sizes are small and the counts are low, because fire alarm circuits carry signalling current rather than power. 18 AWG is common for addressable detection loops and for the wiring between devices, 16 AWG appears where runs are longer or where the system manufacturer specifies it, and 14 AWG is used for notification appliance circuits driving horns, strobes and speakers, because those circuits carry more current and suffer more voltage drop.

Two-conductor cable covers conventional detection zones and simple notification circuits. Three and four conductor cable carries a zone pair plus power, or a data pair plus power, and is the norm for addressable systems that need both communication and 24 V supply in one jacket. Shielded constructions appear where the loop carries data and the environment is electrically noisy, and the shield is normally a foil with a drain wire.

Red is the conventional jacket color in North America, and many authorities having jurisdiction expect it. Other colors exist for specific systems, but on a surplus lot the color is a weak identifier and the print is the strong one.

New York City's retrofit market

New York City has been upgrading fire alarm systems in existing high-rise buildings for decades, driven by local law rather than by new construction. Local Law 5 of 1973 reshaped fire safety requirements for high-rise office buildings, and Local Law 26 of 2004 required sprinkler retrofits and associated fire safety upgrades in older commercial high-rises. Each round of compliance work pulled new cable through buildings that were never designed for it.

That history explains the material. A retrofit in a pre-war or mid-century tower means fishing cable through congested ceiling voids, above plaster ceilings and through shafts that are already full. The cable is ordered in quantity, cut repeatedly, and often left over in short lengths. Plenum-rated cable is frequently required because the ceiling cavity is a return-air path, and the tight spaces mean jackets get scuffed during installation more often than in new work.

The work continues. Building owners replace obsolete control panels, add voice evacuation, upgrade to addressable systems and extend coverage into areas that were previously exempt. Each project produces surplus, and each one produces removed cable that has been in a ceiling for twenty or thirty years.

Why the jacket, not the copper, decides value

Fire alarm cable contains very little copper per foot compared with a feeder, so the metal value is modest. What carries the price is the listing and the condition of the jacket. A full reel of FPLP with a legible print and an intact jacket is a product a fire alarm contractor will buy, because it is exactly what the next retrofit needs and it can be installed without a conduit.

Jacket damage is fatal in a way that it is not on other cable. A plenum cable with a deep scuff, a flattened section or a cut through to the shield cannot be certified as plenum-rated at that point, and an inspector is entitled to reject it. Cable pulled through a ceiling void and then removed is usually abraded along its length, which is why removed fire alarm cable is almost always recovery material regardless of how it looks on the reel.

Circuit integrity cable is a separate case. Where a system must survive a fire for a stated period, cable listed for circuit integrity is used, and it is a heavier, more expensive construction. It is worth identifying precisely, because it is bought on its listing rather than on its copper.

• The rating letters — FPL, FPLR or FPLP — and where they are printed
• AWG and conductor count
• Whether the cable is shielded, and whether it is circuit integrity rated
• Footage, and whether the reel is sealed or has been cut
• Jacket condition, described honestly, including scuffs and flattening